"O Prophet! When you divorce women, divorce them at their 'Iddah (prescribed periods)." Ibn 'Abbas, may Allah be pleased with him, said: "Before their 'Iddah elapses." (Using translation from Nasāʾī 3393)
عَنِ ابْنِ عَبَّاسٍ فِي قَوْلِهِ تَعَالَى {يَا أَيُّهَا النَّبِيُّ إِذَا طَلَّقْتُمُ النِّسَاءَ فَطَلِّقُوهُنَّ لِعِدَّتِهِنَّ} [الطلاق 1] قَالَ ابْنُ عَبَّاسٍ ؓ قُبُلَ عِدَّتِهِنَّ